His attacks on the civilian use of so-called assault weapons raise real questions about his willingness to distort the truth for political purposes. The person nominated to be the nation’s top gun cop shouldn’t use inaccurate descriptions to scare people into supporting gun control.

Mr. Traver is the special agent in charge of the BATFE’s Chicago field division. Therefore, he knows what was covered by the federal assault-weapons ban that sunset in 2004.

But in November 2009, NBC interviewed Traver and reported: “Traver says the power and randomness of the heavy caliber, military-style weapons make them so dangerous not only to people, but to police. They’re so powerful, body armor can’t withstand a hit, and they’re so difficult to control, their bullets often get sprayed beyond the intended targets, striking innocent victims even when they’re in their own homes.”

The list of problems with Mr. Traver’s claims is very long. If he really believes that these weapons fire unacceptably “heavy caliber” bullets, he is going to have to ban virtually all rifles. Small-game rifles — guns designed to kill squirrels and rabbits without destroying too much meat — typically fire .22-caliber bullets, which are only slightly smaller than the .223-caliber bullets fired by the M16 (used by the U.S. military since Vietnam) and the newer M4 carbine (used in the Afghanistan and Iraq wars). Deer-hunting rifles fire rounds that are very similar to those used by the AK-47.

Speaking of M16s, M4s, and AK-47s, Traver is correct when he states that the guns covered by the federal assault-weapons ban were “military-style weapons.” But he fails to note that this really just deals with style — the cosmetics of the guns, not how they actually operate. The guns covered by the ban were not the machine guns actually used by the military, but civilian, semi-automatic versions of those guns. The civilian version of the AK-47 may look like the guns used by militaries around the world, but it is different. It fires essentially the same bullets as deer-hunting rifles at the same rapidity (one bullet per pull of the trigger), and does the same damage.

On penetrating body armor, Mr. Traver leaves out one important detail: Rifles in general are often able to penetrate body armor simply because their bullets travel faster than those fired from handguns. The same can be said for going through the walls of houses. But if he had said that deer-hunting rifles can often penetrate walls and lower-level types of body armor, it is unlikely that his comments would have generated the same fear.

Unfortunately, Mr. Traver has done more than make clearly inaccurate claims about so-called “assault weapons.” He has supported banning .50-caliber rifles, regulations that would force many gun shows to close down, the Chicago handgun ban, and repealing the Tiahrt Amendment, which protects sensitive trace data from being misused in frivolous municipal lawsuits against gun makers. He also worked with the Joyce Foundation, which has funded gun-ban groups such as the Violence Policy Center, on the “Gun Violence Reduction Project.”

John R. Lott's More Guns Less Crime

The fact that Mr. Traver uses the same misleading claims as groups such as the Brady Campaign shouldn’t make it too surprising that gun-control groups are applauding his nomination.

Nor is Traver’s nomination very surprising after President Obama appointed two strong anti-self-defense members to the Supreme Court.

But Mr. Traver’s nomination is quite troubling. Making up claims about guns to demonize them is beyond what is acceptable for someone who wants a position in which he will be regulating American gun ownership.